function func = func_p2p1(d)
% p2p1-Ma1关系方程
r = 1.4;
func = @(Ma1,P) tand(d).^2-(Ma1.^2.*((P.*(r+1)+(r-1))./2./r./Ma1.^2)-1).^2.*...
    (1-((P.*(r+1)+(r-1))./2./r./Ma1.^2))./(1+Ma1.^2.*(r./2+0.5-((P.*(r+1)+(r-1))./2./r./Ma1.^2))).^2./...
    ((P.*(r+1)+(r-1))./2./r./Ma1.^2);
end

